The normal visual acuity is generally set at 1.0, and below 1.0, the visual acuity is considered abnormal, so now a visual acuity check of 0.8 is, statistically speaking, an abnormal kind of vision. For individuals, it also has to be seen in the context of age, because children generally develop their vision to 1.0 or more than 1.0 when they are 8-9 years old. If the vision of children under 8-9 years old does not reach 1.0, it is not necessarily considered abnormal, and it is important to refer to and use as a standard according to the lower limit of vision for each age group. The lower limit of visual acuity is 0.5 for 3-year-olds, 0.6 for 4-5-year-olds, 0.7 for 6-year-olds, and 0.8 for 7-year-olds and above, so for 10-year-olds, a visual acuity of 0.8 is a bit low, so consider whether there is a possibility of mild myopia. This is normal. You can observe the progress of vision every six months, if the vision does not change with the growth of age, further examination should be done to rule out the possibility of delayed vision development.